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Somatoform Disorders
Somatoform Disorders Jo¨rg Angenendt, University Medical Center, University Hospital Freiburg, Freiburg, Germany Martin Ha¨rter, Center for Psychosocial Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany Ó 2015 Elsevier Ltd. All rights reserved.
Abstract Somatoform disorders, or somatic symptom disorder, as it is denominated in Diagnostic and Statistical Manual of Mental Disorders, fifth edition, are a heterogeneous group of mental health problems that are characterized by enduring bodily complaints and symptoms that are not due to organic dysfunction or disease. These patients perceive a wide range of severe symptoms like pain, gastrointestinal, cardiovascular, sexual, and/or pseudoneurological symptoms, which cause permanent attention, worry, and distress. They excessively seek medical help and reassurance, but have difficulties accepting the nonpathological results in medical examinations. The concept of psychological and psychosocial influences and causes is rejected, and mental health services are usually not attended. Biological, psychological, and psychosocial factors interact as precipitating, triggering, and maintaining factors of psychopathology. The different subtypes (somatization, conversion, pain disorders, hypochondriasis, and dysmorphophobia) are described with their central features: clinical presentation, epidemiology, comorbidity, and course. Current etiological and pathogenic models are introduced as a clinical and theoretical basis for therapeutic interventions. Besides general psychotherapeutic principles more specific interventions addressing the modification of subjective health-beliefs, illness behaviors, and coping skills are described. The clinical significance of somatoform disorders stresses the need for training programs to provide and improve basic diagnostic and therapeutic skills, especially in primary care. Future directions for the management of these disorders are outlined.
Introduction The history of somatization phenomena, the ‘borderland between medicine and psychiatry’ (Lipowski, 1988), or in terms of neuroscience the problem of the ‘body–brain-interface’ (Guggenheim, 2000), can be traced back to ancient Greek medicine. Here the term ‘hysteria’ was used to describe patients’ somatic complaints without the presence of somatic disease. Hysteria (from hystera ¼ womb) was understood as a psychological problem in women, whose intrapsychic conflicts, resulting from the unfulfilled wish to bear a child, lead to somatic complaints (see Hysteria: History and Critiques). Similar clinical observations by different European clinicians since the mid-nineteenth century (Briquet, Charcot, Janet, Breuer) were antecedents of the Freudian concept of conversion disorder. The psychodynamic etiology and psychoanalytic treatment approach to patients with conversion disorders, ‘functional’ or psychosomatic complaints, and hysteria was most influential to the 1970s. Since 1980 the term somatoform disorders had replaced the traditionally used, but not precisely defined above mentioned terms of hysteria, that were mainly confounded with etiological (psychoanalytical) assumptions. Currently in Diagnostic and Statistical Manual of Mental Disorders (fifth edition) (DSM-V; APA, 2013) the term was changed into ‘somatic symptom disorder’. The concept of somatoform disorders encompasses a heterogeneous group of psychiatric disorders that are characterized by three core features: (1) patients suffer from enduring or recurrent bodily complaints, symptoms and/or pain (e.g., palpitations, headache, fatigue, and dizziness), which are experienced as indicators of somatic illness, (2) psychological and social factors – usually refused as major influencing factors by the patients – play a predominant role in the development and course of these disorders, and (3) patients experience a general preoccupation with bodily symptoms and health concerns. In DSM-IV and the tenth
10
edition of International Classification of Diseases (ICD-10) the requirement, that somatic symptoms must be ‘medically unexplained’ was a central diagnostic prerequisite, which is eliminated in the current DSM version. This article describes the various subtypes of somatoform disorders, their prevalence, and etiology. Critical aspects regarding diagnosis, treatment, and management of somatoform disorders in healthcare systems will be discussed.
Classification and Epidemiology From a nosological perspective, somatoform disorders were grouped together in DSM-III in 1980 for the first time. However, this clustering was primarily based on clinical criteria and not on empirically derived or laboratory findings. The ICD-10 includes most of the somatoform disorders of the DSM-IV (American Psychiatric Association, 1994), except for conversion disorders that are grouped with the dissociative disorders. The main feature of these disorders is the “repeated presentation of physical symptoms with persistent request for medical investigations, in spite of repeated negative findings and reassurances by doctors that these symptoms are not primarily due to somatic illness. If somatic disorders are present, they do not explain the nature and the extent of the symptoms or the distress and preoccupations of the patient” (WHO, 1991). For the diagnosis of all somatoform disorders the patients’ symptoms have to be of sufficient severity to warrant clinical attention. The ICD-10 differentiates between four main nosological entities (seven different diagnoses) which were characterized by different diagnostic criteria (see Table 1). Recurrent, multiple somatic complaints that are not associated with any physical disorder are the essential feature of somatization disorder. The diagnosis requires a history of many bodily symptoms of several years’ duration with onset
International Encyclopedia of the Social & Behavioral Sciences, 2nd edition, Volume 23
http://dx.doi.org/10.1016/B978-0-08-097086-8.27069-4
Somatoform Disorders
Table 1
11
Somatoform disorders and their characteristics
Subtypes
Characteristics and (selected) main criteria (ICD-10)
Somatization disorder
l l l l
Hypochondriasis
l l
Somatoform autonomic dysfunction
l l
Persistent somatoform pain disorder
l
A history of at least 2 years of multiple and variable complaints which cannot be better explained by somatic factors or other psychiatric disorders (A) Preoccupation with the symptoms causes persistent distress and leads to seek repeated medical consultations (B) Persistent refusal to accept medical reassurance that there is no adequate physical cause (C) A total of six or more enduring autonomous symptoms from different groups (gastrointestinal, cardiovascular, genitourinary system, skin and pain symptoms) (D) A persistent belief of the presence of a serious physical disease (A1) A persistent preoccupation with a presumed deformity or disfigurement (body dysmorphic disorder) (A2) Symptoms of autonomic arousal attributed by the patient to a physical disorder (heart and cardiovascular system/upper and lower gastrointestinal tract/respiratory or genitourinary system) (A) Two or more autonomic symptoms like palpitations, sweating, dry mouth, flushing or blushing, epigastric discomfort etc. (B) Persistence of severe and distressing pain for at least 6 months which cannot be explained adequately by a physiological process or physical disorder (A)
before the age of 30. In somatoform autonomic dysfunctions symptoms of autonomic arousal (e.g., palpitations, sweating, and stomach discomfort) are the main complaints of the patients. Chronic pain syndromes (duration >6 months) like tension headache, lower back pain, and atypical facial pain are labeled as persistent somatoform pain disorder. Excessive and dispropriate thoughts, feelings, and behaviors can play either a major role within a general medical condition (e.g., rheumatoid arthritis) or may be the only determinants of pain (e.g., not otherwise specified lower back pain). The pain in one or more anatomical sites is the main focus of clinical presentation. Conversion disorder is mostly a transient disturbance of physical functions (typically occurring in stressful situations) which do not conform to current concepts of the anatomy and physiology of the nervous system. Many disorders seem to be neurological disorders (e.g., motor disorders or disturbances of sensory function), but do not show the usual pathological signs. Hypochondriasis is not exclusively a secondary phenomenon within affective, anxiety, or psychotic disorders but a diagnostic subgroup of its own. Patients are preoccupied with their belief of already suffering from a severe illness or the fear of becoming ill with a life-threatening disease (e.g., cancer, stroke, or AIDS). The diagnostic congregation of body dysmorphic disorder – which is rarely seen as a full-blown syndrome – is different in the nosological systems. In the ICD-10 it is a subgroup of hypochondriasis, with the preoccupation on a presumed deformity or body abnormality. Patients subjectively feel unattractive, ugly, and disfigured despite lacking evidence for major defects in appearance or stigmata. Positive feedback from significant others about normality in appearance has no corrective effects. Somatoform disorders show high prevalence rates in the community, especially in the primary health care system. In industrialized societies up to 4–19% in the general population suffer from somatoform disorders (Hiller et al., 2006; Simon and von Korff, 1991). In medical outpatient and inpatient treatment, patients with the probable diagnosis of somatoform disorders are estimated at up to 25–30%. The onset is in adolescence or young adulthood, and the course in untreated cases is usually chronic with a waxing and waning of
symptoms. Women, persons from lower social classes, and ethnic subgroups are more likely to develop somatoform disorder. Furthermore, somatization is more often seen after separation and divorce. Somatoform disorders are often associated with other psychiatric disorders, especially depression, anxiety disorders, substance abuse disorders, and personality disorders (see Depression; Anxiety and Anxiety Disorders; Personality Disorders). Patients with somatoform disorders are often not correctly recognized in primary care and therefore insufficiently treated. The latency between the onset of the disorder, the appropriate diagnosis, and the referral to adequate treatment is usually high. These factors lead to largely extended costs for medical and psychosocial services (14-fold costs of care than average costs of outpatients and sixfold costs in inpatients) (Barsky et al., 2005).
Etiology and Course No single factor can explain the pathogenesis of somatoform disorders. Comparable with other psychiatric disorders, biological, psychological, and social factors interact in complex ways (see Mental Illness, Etiology of). Their impact probably varies over time within the same individual and between different patients resulting in a common final pathway. There is no general etiological model for somatization phenomena (Rief and Broadbent, 2007). However, interesting neurobiological studies demonstrate that patients with somatization disorder may have an abnormality in cortical and neuropsychological functioning, e.g., bifrontal impairment of the hemispheres, abnormal auditory-evoked potentials, and abnormal levels of cortisol (Rief et al., 2010; Tak and Rosmalen, 2010). Several etiological conditions play a prominent role, especially in maintaining the process and can be considered as empirically derived risk factors (see Figure 1). 1. Genetic risks, e.g., higher rates of somatoform disorders for monozygot than for dizygot twins, and in first-degree relatives. 2. Higher physiological reactivity which can lead to pervasive interoception of physiological signs. Unspecific bodily
12
Somatoform Disorders
Figure 1 Risk model for somatoform disorders. Adapted from Rief, W., Hiller, W., 1998. Somatisierungsstörung und Hypochondrie (Somatization Disorder amd Hypochondriasis). Hogrefe, Göttingen.
3.
4.
5.
6.
sensations are perceived and interpreted as symptoms of disease. The consequence is the intensification of the complaints and elevated attention to them. Biographic vulnerability, a high proportion of physical, sexual abuse (within the family), and traumatic experiences like war and natural catastrophes are overrepresented in these patients. Furthermore, chronically ill parents or siblings, and learning by model within the family may influence the localization and types of somatoform symptoms. Personality traits, e.g., difficulties in the perception and expression of emotions (alexithymia) with an inverse relationship of reduced emotional expressions and heightened psychophysiological arousal in stressful situations. Unrealistic health beliefs with a low tolerance for normal complaints, ‘catastrophizing’ ideas about physiological processes, and exaggerated expectations regarding effects of modern medicine to all kinds of complaints. Chronification factors like multiple diagnostic procedures, the overvaluation of normal variants through the caring physician (iatrogen factors) and positive (e.g., attention from others) or negative reinforcement (e.g., defense mechanism for negative emotions, advantages of the sickrole, withdrawal from responsibilities).
Which of these potential factors are important, and how much impact they have in the individual patient have to be
determined within the diagnostic and psychotherapeutic process (see Mental Illness, Etiology of).
Diagnostic Process The diagnostic process follows a sequence starting with a careful monitoring of all presented bodily complaints and ending up with a reliable and valid diagnosis of a specific subtype of somatoform disorder and its severity (Schaefert et al., 2012). The knowledge of base rates for somatoform disorders and potential severe medical disorders which have to be ruled out, age of the patients, and their presentation style, history of other bodily complaints and excessive visits to other doctors might be hints for the assumption of the diagnosis. The physician is confronted with the dilemma of possible false decisions: (1) they might diagnose somatoform disorder although the symptoms are better explained by a somatic disease which has to be treated by medical guidelines (type-1 error, ‘false positive’). As a consequence patients might not receive appropriate medical treatment and might feel stigmatized as mentally ill. (2) The diagnosis of a somatic disease/ dysfunction is assumed although the patient suffers from a somatoform disorder (type-2 error; ‘false negative’). In most cases doctors and patients judge the risk of missing the correct
Somatoform Disorders
somatic diagnosis as more adverse and therefore try to minimize it. However, this can be one of the major factors maintaining somatoform disorders. A pragmatic rule for diagnosis is “to have somatic diagnostic efforts as much as necessary but as less as possible.” Thorough, but not excessive or indefinite, medical examinations have to rule our severe and harmful organic disease and dysfunctions that might be causing the symptoms (e.g., hyperparathyroidism, multiple sclerosis, or brain tumor). It has to be supported by adequate and plausible procedures (e.g., physical and neurological examination, laboratory examination). Results and documents from other doctors should be revised in order to prevent repeated examination without relevance. A precise mental health examination for a complete overview of previous severe psychiatric disorders and minor complaints and the current psychopathological status is necessary. In single cases it can be difficult to decide whether the symptoms can better be explained by affective, anxiety, and personality disorders or whether they are real comorbid states. The probability of comorbid diagnoses positively correlates with symptom severity of somatoform disorders. The sequence over time and the severity of symptoms are helpful in finding the correct hierarchy. Symptoms, pathological illness behavior, course, and consequence of the complaints will allow one to find the adequate nosological diagnoses along with the operationalized diagnostic criteria. This diagnosis within the group of somatoform disorder has the status of a working hypothesis and is needed for concrete treatment planning. If the patient visits a mental health specialist he or she will gather specific information regarding nosological diagnosis. A sophisticated analysis of all relevant information concerning the individual development, learning, and predisposing factors, the onset, and further course of the symptoms, which is based on a life-chart interview, and information about actual psychosocial conditions, conflicts, and traumata is inevitable. Of course it partly depends on the theoretical assumptions and etiological models of the different psychotherapeutic schools (see Differential Diagnosis in Psychiatry).
Treatment Because psychological factors are most influential in the development and course of somatoform disorders they have to be addressed in every effective treatment. Of course the setting, intensity, and content of psychological interventions can vary depending on factors like severity of symptoms (duration, intensity, functional impairments), comorbidity, insight, and motivation of the patient and availability of psychotherapy. In a step-by-step approach the primary care physician should start with short-term verbal interventions. Acute and isolated somatoform symptoms may respond to psychoeducation and counseling within the usual medical visits. Counseling and advice for general and easy-to-administer methods of symptom monitoring and management can be helpful. The physician should know the pitfalls in the treatment of patients with somatoform disorders and avoid procedures, which might reinforce the patients’ pathological illness behaviors (e.g., no medical tests or laboratory examinations without clear indication). Information about and motivation for more specific
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forms of psychotherapy are essential if these basic interventions within the primary care system are not sufficient. For the more severe patients a referral to mental health experts is needed, for chronic and therapy-refractory cases even psychiatric or psychosomatic inpatient treatment may be necessary. Unspecific factors, which are important in any psychotherapy (e.g., therapeutic alliance, expectations of being helped, enhancing the sense of mastery, etc.) can be differentiated from specific therapeutic techniques and be adapted to relevant pathological processes in somatoform disorders (see below). Multimodal and multidisciplinary treatment approaches seem to be more effective than single treatment approaches (Mayou et al., 1995). A validating, accepting, and (especially in the beginning) nonconfronting patient–therapist relationship is a prerequisite for active participation in therapy. It is also the basis for the development of an alternative, holistic model of illness, the motivation to change, and active participation in therapy. Selfmonitoring diaries aim at a precise identification of symptoms in relation to external or interoceptive stimuli, events, and their positive and negative consequences in concrete situations. Psychoeducation and cognitive therapy are essential for a critical discussion and revision of inadequate concepts about health and disease and a better understanding of ongoing mechanisms. For example, the hypochondriac patient may realize the effects of a feedback loop leading to a vicious circle as is the case in increased autonomic arousal through anxious thoughts and worries about illness. In a collaborative way the therapist tries to convey a more realistic and helpful paradigm of body–mind interactions which aims at a better understanding and mastery of symptoms. Relaxation training, breathing exercises, or mindfulness-based interventions are introduced as methods for an active reduction of tension, arousal, and apprehension. The patient is motivated to reduce maladaptive illness behaviors like body scanning and checking, excessive medical visits, seeking reassurance, and social withdrawal. Cooperation with physicians and family members is warranted so that they can avoid inadequate reactions to the patients’ illness behaviors. Alternative behaviors, e.g., exercises, sports, and positive activities have to replace the symptomatic ones and can help to re-experience bodily functions in a more positive way. Stress management, social competence, and problem-solving interventions can be used optionally to improve coping with stress, conflicts, and interpersonal problems. Furthermore, therapy has to prevent relapses and enhance a more balanced life style. As some of the symptoms might resist the described interventions or take a longer time to be effective, patients have to learn how to ‘live with the residual complaints as best as possible’ and to regain a better quality of life instead of waiting for complete remission. Up to now there is no empirically validated form of specific pharmacological therapy. Clinical experience shows that in some cases tricyclic antidepressants and selective-serotonininhibitors might be helpful, especially in patients with comorbid depression, anxiety disorders, and pain. However, without concomitant psychotherapy the risk of relapse is usually high. Benzodiazepines and low-potency neuroleptics should not be given because of the risks of long-term intake, especially abuse and dependency in benzodiazepines and tardive dyskinesia in neuroleptics.
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Somatoform Disorders
Compared to other psychiatric disorders the empirical evidence for effective treatments is still low in somatoform disorders. But there is a growing number of controlled outcome studies since the syndromes were clearly defined in 1980. These studies have to face the fact that most of these patients are not treated within mental health services but in the primary care system or in consultation and liaison services. Additional difficulties arise from the complexity of recent approaches, which can only be evaluated as ‘total treatment packages’ (see Antidepressant Drugs; Behavior Therapy: Psychiatric Aspects).
Summary and Outlook The clearer operationalization of diagnoses within DSM and ICD classification systems stimulated a lot of empirical studies concerning the epidemiology, etiology, pathogenesis, and treatment of somatoform disorders in the last three decades. Medical and mental health services have realized the clinical relevance of these disorders and the need for early recognition, collaborative, stepped-care, and multidisciplinary intervention programs (Schaefert et al., 2012). Clinical observations and outcome studies have challenged the former statement, that patients with somatoform disorders in general have a poor prognosis. The acceptance of empirically based psychotherapeutic and psychiatric interventions can be enhanced if their positive effects are transparent to the patient. Convincing models for a better explanation and understanding of symptoms, the definition of limited and concrete treatment goals, and the provision of successful experiences in symptom reduction and improving coping abilities may have the function of a ‘positive vicious circle’ and convey a sense of mastery. However, patients and their caregivers have to overcome a series of obstacles: 1. The first step is the correct recognition and early diagnosis by the primary care physician. 2. Divergent health belief systems of patient and physician may burden the relationship and cooperation between them, so that it is difficult to realize psychological interventions. 3. Although psychological treatment is indicated, physicians often avoid time-consuming verbal interventions or are not adequately trained for their application. However, it is not clear whether psychotherapeutic interventions, which are proven within a psychotherapeutic context, can be adopted to primary care without diminishing their efficacy. 4. If physicians try to refer to mental health experts a lot of patients refuse this referral (e.g., for reasons of stigma) or are not motivated for psychotherapy. Since empirical validation of treatment approaches for subtypes of somatoform disorders is still different, the selection of therapeutic methods often depends on local availability and personal preferences rather than on evidence-based criteria. Each of these items is a challenge for clinical and research efforts as well as for a better dissemination of existing knowledge and competence to different health professionals who are involved in the treatment of somatoform patients. Since the first edition of this text a lot of empirical studies have
contributed to our knowledge and are congregated in some meta-analyses and Cochrane reviews. In the last decade a controversial debate concerning the nosological congregation in somatoform, related disorders and their diagnostic criteria (Rief and Hiller, 1999) was ongoing. Since the introduction of the modified concept of ‘somatic symptom disorder’ in DSM-V it is even more pronounced. Especially the elimination of the requirement that symptoms must be ‘medically unexplained’ is criticized. Prominent researchers call the DSM-V concept as poorly tested and as too ‘loose’. In the case of ‘false positive diagnosis’ the patient has to bear the burden of severe or harmful consequences, especially if underlying medical causes are missed and not treated adequately. Additionally many patients maybe ‘mislabeled as mentally ill’ (Frances, 2013). High rates of mutual comorbidity between anxiety, affective, substance abuse, and somatoform disorders have challenged the usefulness of the concept of discrete and stable nosological entities and different treatment needs. Some clinicians had proposed a concept of spectrum disorders with more transient borderlines between different, but obviously linked, clusters of psychopathology and their courses in a long-term perspective. Specifically the relevance of subclinical forms of disorders as precursors and remaining psychopathological states after partial remission is stressed. Some recent candidates are thought to be potentially affiliated as psychiatric diseases with apparent parallels to somatoform disorders. Chronic fatigue syndrome, fibromyalgia, and multiple chemistry sensitivity, etc. are syndromes with bodily complaints of unknown etiology and pathogenesis. Their treatment might profit from adopting interventions, which have been successfully applied in somatoform disorders.
See also: Fear: Psychological and Neural Aspects; Freud, Sigmund (1856–1939); Hysteria: History and Critiques; Janet, Pierre (1859–1947); Normality and Mental Health; Psychosomatic Medicine; Stress, Coping and Health.
Bibliography American Psychiatric Association, 1994. Diagnostic and Statistical Manual of Mental Disorders: DSM-IV, fourth ed. American Psychiatric Association, Washington, DC. American Psychiatric Association, 2013. Diagnostic and Statistical Manual of Mental Disorders: DSM-V, fifth ed. American Psychiatric Association, Washington, DC. Barsky, A.,J., Orav, E.J., Bates, D.W., 2005. Somatization increases medical utilization and costs independent of psychiatric and medical comorbidity. Archives of General Psychiatry 62, 903–910. Bass, C.M., Murphy, M.R., 1990. Somatization disorder: critique of the concept and suggestions for future research. In: Bass, C. (Ed.), Somatization: Physical Symptoms and Psychological Illness. Blackwell, Oxford, UK, pp. 301–332. Frances, A., 2013. The new somatic symptom disorder in DSM-5 risks mislabeling many people as mentally ill. British Medical Journal 346, f1580. http://dx.doi.org/ 10.1136/bmj.f1580 (Published 20 March 2013). Guggenheim, F.G., 2000. Somatoform disorders. In: Saddock, B.J., Saddock, V.A. (Eds.), Comprehensive Textbook of Psychiatry. Lippincott Williams and Wilkins, Philadelphia, PA, pp. 1504–1532. Hiller, W., Rief, W., Brähler, E., 2006. Somatization in the population: from mild bodily misperceptions to disabling symptoms. Social Psychiatry and Psychiatric Epidemiology 41, 704–712.
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Kellner, R., 1985. Functional somatic symptoms and hypochondriasis. Archives of General Psychiatry 42, 821–833. Lipowski, Z.J., 1988. Somatization. The concept and its clinical application. American Journal of Psychiatry 145, 1358–1368. Mayou, R., Creed, F., Sharpe, M., 1995. Treatment of Functional Physical Symptoms. Oxford University Press, Oxford, UK. Olde Hartmann, T.C., Borghuis, M.S., Lucassen, P.L., van der Laar, F.A., Speckens, A.E., van Weel, C., 2009. Medically unexplained symptoms, somatization disorder and hypochondriasis: course and prognosis. A systematic review. Journal of Psychosomatic 71, 325–334. Pilowsky, I., 1997. Abnormal Illness Behaviour. Wiley, Chichester, UK. Rief, W., Hiller, W., 1999. Toward empirically based criteria for the classification of somatoform disorders. Journal of Psychosomatic Research 46, 507–518. Rief, W., Hiller, W., 1998. Somatisierungsstörung und Hypochondrie (Somatization Disorder amd Hypochondriasis). Hogrefe, Göttingen. Rief, W., Nanke, A., 1999. Somatization disorder from a cognitive-psychobiological perspective. Current Opinion in Psychiatry 12, 733–738.
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Rief, W., Broadbent, E., 2007. Explaining medically unexplained symptoms – models and mechanisms. Clinical Psychology Review 27, 821–841. Rief, W., Hennings, A., Riemer, S., Euteneuer, F., 2010. Psychobiological differences between depression and somatization. Journal of Psychosomatic Research 68 (5), 495–502. Schaefert, R., Hausteiner-Wiehle, C., Häuser, W., Ronel, J., Herrmann, M., Hennigsen, P., 2012. Clinical practice guideline: non-specific, functional and somatoform bodily complaints: Dtsch. Ärzteblatt International 109 (47), 803–813. http://dx.doi.org/10.3238/arztebl.2012.0803. Simon, G.E., von Korff, M., 1991. Somatization and psychiatric disorder in the NIMH epidemiologic catchment area study. American Journal of Psychiatry 148, 1494–1500. Tak, L.M., Rosmalen, J.G., 2010. Dysfunction of stress responsive systems as a risk factor for functional somatic syndromes. Journal of Psychosomatic Research 68, 461–468. World Health Organization, 1991. International Classification of Diseases (ICD-10). WHO, Geneva.
Abstract Somatoform disorders, or somatic symptom disorder, as it is denominated in Diagnostic and Statistical Manual of Mental Disorders, fifth edition, are a heterogeneous group of mental health problems that are characterized by enduring bodily complaints and symptoms that are not due to organic dysfunction or disease. These patients perceive a wide range of severe symptoms like pain, gastrointestinal, cardiovascular, sexual, and/or pseudoneurological symptoms, which cause permanent attention, worry, and distress. They excessively seek medical help and reassurance, but have difficulties accepting the nonpathological results in medical examinations. The concept of psychological and psychosocial influences and causes is rejected, and mental health services are usually not attended. Biological, psychological, and psychosocial factors interact as precipitating, triggering, and maintaining factors of psychopathology. The different subtypes (somatization, conversion, pain disorders, hypochondriasis, and dysmorphophobia) are described with their central features: clinical presentation, epidemiology, comorbidity, and course. Current etiological and pathogenic models are introduced as a clinical and theoretical basis for therapeutic interventions. Besides general psychotherapeutic principles more specific interventions addressing the modification of subjective health-beliefs, illness behaviors, and coping skills are described. The clinical significance of somatoform disorders stresses the need for training programs to provide and improve basic diagnostic and therapeutic skills, especially in primary care. Future directions for the management of these disorders are outlined.
Introduction The history of somatization phenomena, the ‘borderland between medicine and psychiatry’ (Lipowski, 1988), or in terms of neuroscience the problem of the ‘body–brain-interface’ (Guggenheim, 2000), can be traced back to ancient Greek medicine. Here the term ‘hysteria’ was used to describe patients’ somatic complaints without the presence of somatic disease. Hysteria (from hystera ¼ womb) was understood as a psychological problem in women, whose intrapsychic conflicts, resulting from the unfulfilled wish to bear a child, lead to somatic complaints (see Hysteria: History and Critiques). Similar clinical observations by different European clinicians since the mid-nineteenth century (Briquet, Charcot, Janet, Breuer) were antecedents of the Freudian concept of conversion disorder. The psychodynamic etiology and psychoanalytic treatment approach to patients with conversion disorders, ‘functional’ or psychosomatic complaints, and hysteria was most influential to the 1970s. Since 1980 the term somatoform disorders had replaced the traditionally used, but not precisely defined above mentioned terms of hysteria, that were mainly confounded with etiological (psychoanalytical) assumptions. Currently in Diagnostic and Statistical Manual of Mental Disorders (fifth edition) (DSM-V; APA, 2013) the term was changed into ‘somatic symptom disorder’. The concept of somatoform disorders encompasses a heterogeneous group of psychiatric disorders that are characterized by three core features: (1) patients suffer from enduring or recurrent bodily complaints, symptoms and/or pain (e.g., palpitations, headache, fatigue, and dizziness), which are experienced as indicators of somatic illness, (2) psychological and social factors – usually refused as major influencing factors by the patients – play a predominant role in the development and course of these disorders, and (3) patients experience a general preoccupation with bodily symptoms and health concerns. In DSM-IV and the tenth
10
edition of International Classification of Diseases (ICD-10) the requirement, that somatic symptoms must be ‘medically unexplained’ was a central diagnostic prerequisite, which is eliminated in the current DSM version. This article describes the various subtypes of somatoform disorders, their prevalence, and etiology. Critical aspects regarding diagnosis, treatment, and management of somatoform disorders in healthcare systems will be discussed.
Classification and Epidemiology From a nosological perspective, somatoform disorders were grouped together in DSM-III in 1980 for the first time. However, this clustering was primarily based on clinical criteria and not on empirically derived or laboratory findings. The ICD-10 includes most of the somatoform disorders of the DSM-IV (American Psychiatric Association, 1994), except for conversion disorders that are grouped with the dissociative disorders. The main feature of these disorders is the “repeated presentation of physical symptoms with persistent request for medical investigations, in spite of repeated negative findings and reassurances by doctors that these symptoms are not primarily due to somatic illness. If somatic disorders are present, they do not explain the nature and the extent of the symptoms or the distress and preoccupations of the patient” (WHO, 1991). For the diagnosis of all somatoform disorders the patients’ symptoms have to be of sufficient severity to warrant clinical attention. The ICD-10 differentiates between four main nosological entities (seven different diagnoses) which were characterized by different diagnostic criteria (see Table 1). Recurrent, multiple somatic complaints that are not associated with any physical disorder are the essential feature of somatization disorder. The diagnosis requires a history of many bodily symptoms of several years’ duration with onset
International Encyclopedia of the Social & Behavioral Sciences, 2nd edition, Volume 23
http://dx.doi.org/10.1016/B978-0-08-097086-8.27069-4
Somatoform Disorders
Table 1
11
Somatoform disorders and their characteristics
Subtypes
Characteristics and (selected) main criteria (ICD-10)
Somatization disorder
l l l l
Hypochondriasis
l l
Somatoform autonomic dysfunction
l l
Persistent somatoform pain disorder
l
A history of at least 2 years of multiple and variable complaints which cannot be better explained by somatic factors or other psychiatric disorders (A) Preoccupation with the symptoms causes persistent distress and leads to seek repeated medical consultations (B) Persistent refusal to accept medical reassurance that there is no adequate physical cause (C) A total of six or more enduring autonomous symptoms from different groups (gastrointestinal, cardiovascular, genitourinary system, skin and pain symptoms) (D) A persistent belief of the presence of a serious physical disease (A1) A persistent preoccupation with a presumed deformity or disfigurement (body dysmorphic disorder) (A2) Symptoms of autonomic arousal attributed by the patient to a physical disorder (heart and cardiovascular system/upper and lower gastrointestinal tract/respiratory or genitourinary system) (A) Two or more autonomic symptoms like palpitations, sweating, dry mouth, flushing or blushing, epigastric discomfort etc. (B) Persistence of severe and distressing pain for at least 6 months which cannot be explained adequately by a physiological process or physical disorder (A)
before the age of 30. In somatoform autonomic dysfunctions symptoms of autonomic arousal (e.g., palpitations, sweating, and stomach discomfort) are the main complaints of the patients. Chronic pain syndromes (duration >6 months) like tension headache, lower back pain, and atypical facial pain are labeled as persistent somatoform pain disorder. Excessive and dispropriate thoughts, feelings, and behaviors can play either a major role within a general medical condition (e.g., rheumatoid arthritis) or may be the only determinants of pain (e.g., not otherwise specified lower back pain). The pain in one or more anatomical sites is the main focus of clinical presentation. Conversion disorder is mostly a transient disturbance of physical functions (typically occurring in stressful situations) which do not conform to current concepts of the anatomy and physiology of the nervous system. Many disorders seem to be neurological disorders (e.g., motor disorders or disturbances of sensory function), but do not show the usual pathological signs. Hypochondriasis is not exclusively a secondary phenomenon within affective, anxiety, or psychotic disorders but a diagnostic subgroup of its own. Patients are preoccupied with their belief of already suffering from a severe illness or the fear of becoming ill with a life-threatening disease (e.g., cancer, stroke, or AIDS). The diagnostic congregation of body dysmorphic disorder – which is rarely seen as a full-blown syndrome – is different in the nosological systems. In the ICD-10 it is a subgroup of hypochondriasis, with the preoccupation on a presumed deformity or body abnormality. Patients subjectively feel unattractive, ugly, and disfigured despite lacking evidence for major defects in appearance or stigmata. Positive feedback from significant others about normality in appearance has no corrective effects. Somatoform disorders show high prevalence rates in the community, especially in the primary health care system. In industrialized societies up to 4–19% in the general population suffer from somatoform disorders (Hiller et al., 2006; Simon and von Korff, 1991). In medical outpatient and inpatient treatment, patients with the probable diagnosis of somatoform disorders are estimated at up to 25–30%. The onset is in adolescence or young adulthood, and the course in untreated cases is usually chronic with a waxing and waning of
symptoms. Women, persons from lower social classes, and ethnic subgroups are more likely to develop somatoform disorder. Furthermore, somatization is more often seen after separation and divorce. Somatoform disorders are often associated with other psychiatric disorders, especially depression, anxiety disorders, substance abuse disorders, and personality disorders (see Depression; Anxiety and Anxiety Disorders; Personality Disorders). Patients with somatoform disorders are often not correctly recognized in primary care and therefore insufficiently treated. The latency between the onset of the disorder, the appropriate diagnosis, and the referral to adequate treatment is usually high. These factors lead to largely extended costs for medical and psychosocial services (14-fold costs of care than average costs of outpatients and sixfold costs in inpatients) (Barsky et al., 2005).
Etiology and Course No single factor can explain the pathogenesis of somatoform disorders. Comparable with other psychiatric disorders, biological, psychological, and social factors interact in complex ways (see Mental Illness, Etiology of). Their impact probably varies over time within the same individual and between different patients resulting in a common final pathway. There is no general etiological model for somatization phenomena (Rief and Broadbent, 2007). However, interesting neurobiological studies demonstrate that patients with somatization disorder may have an abnormality in cortical and neuropsychological functioning, e.g., bifrontal impairment of the hemispheres, abnormal auditory-evoked potentials, and abnormal levels of cortisol (Rief et al., 2010; Tak and Rosmalen, 2010). Several etiological conditions play a prominent role, especially in maintaining the process and can be considered as empirically derived risk factors (see Figure 1). 1. Genetic risks, e.g., higher rates of somatoform disorders for monozygot than for dizygot twins, and in first-degree relatives. 2. Higher physiological reactivity which can lead to pervasive interoception of physiological signs. Unspecific bodily
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Somatoform Disorders
Figure 1 Risk model for somatoform disorders. Adapted from Rief, W., Hiller, W., 1998. Somatisierungsstörung und Hypochondrie (Somatization Disorder amd Hypochondriasis). Hogrefe, Göttingen.
3.
4.
5.
6.
sensations are perceived and interpreted as symptoms of disease. The consequence is the intensification of the complaints and elevated attention to them. Biographic vulnerability, a high proportion of physical, sexual abuse (within the family), and traumatic experiences like war and natural catastrophes are overrepresented in these patients. Furthermore, chronically ill parents or siblings, and learning by model within the family may influence the localization and types of somatoform symptoms. Personality traits, e.g., difficulties in the perception and expression of emotions (alexithymia) with an inverse relationship of reduced emotional expressions and heightened psychophysiological arousal in stressful situations. Unrealistic health beliefs with a low tolerance for normal complaints, ‘catastrophizing’ ideas about physiological processes, and exaggerated expectations regarding effects of modern medicine to all kinds of complaints. Chronification factors like multiple diagnostic procedures, the overvaluation of normal variants through the caring physician (iatrogen factors) and positive (e.g., attention from others) or negative reinforcement (e.g., defense mechanism for negative emotions, advantages of the sickrole, withdrawal from responsibilities).
Which of these potential factors are important, and how much impact they have in the individual patient have to be
determined within the diagnostic and psychotherapeutic process (see Mental Illness, Etiology of).
Diagnostic Process The diagnostic process follows a sequence starting with a careful monitoring of all presented bodily complaints and ending up with a reliable and valid diagnosis of a specific subtype of somatoform disorder and its severity (Schaefert et al., 2012). The knowledge of base rates for somatoform disorders and potential severe medical disorders which have to be ruled out, age of the patients, and their presentation style, history of other bodily complaints and excessive visits to other doctors might be hints for the assumption of the diagnosis. The physician is confronted with the dilemma of possible false decisions: (1) they might diagnose somatoform disorder although the symptoms are better explained by a somatic disease which has to be treated by medical guidelines (type-1 error, ‘false positive’). As a consequence patients might not receive appropriate medical treatment and might feel stigmatized as mentally ill. (2) The diagnosis of a somatic disease/ dysfunction is assumed although the patient suffers from a somatoform disorder (type-2 error; ‘false negative’). In most cases doctors and patients judge the risk of missing the correct
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somatic diagnosis as more adverse and therefore try to minimize it. However, this can be one of the major factors maintaining somatoform disorders. A pragmatic rule for diagnosis is “to have somatic diagnostic efforts as much as necessary but as less as possible.” Thorough, but not excessive or indefinite, medical examinations have to rule our severe and harmful organic disease and dysfunctions that might be causing the symptoms (e.g., hyperparathyroidism, multiple sclerosis, or brain tumor). It has to be supported by adequate and plausible procedures (e.g., physical and neurological examination, laboratory examination). Results and documents from other doctors should be revised in order to prevent repeated examination without relevance. A precise mental health examination for a complete overview of previous severe psychiatric disorders and minor complaints and the current psychopathological status is necessary. In single cases it can be difficult to decide whether the symptoms can better be explained by affective, anxiety, and personality disorders or whether they are real comorbid states. The probability of comorbid diagnoses positively correlates with symptom severity of somatoform disorders. The sequence over time and the severity of symptoms are helpful in finding the correct hierarchy. Symptoms, pathological illness behavior, course, and consequence of the complaints will allow one to find the adequate nosological diagnoses along with the operationalized diagnostic criteria. This diagnosis within the group of somatoform disorder has the status of a working hypothesis and is needed for concrete treatment planning. If the patient visits a mental health specialist he or she will gather specific information regarding nosological diagnosis. A sophisticated analysis of all relevant information concerning the individual development, learning, and predisposing factors, the onset, and further course of the symptoms, which is based on a life-chart interview, and information about actual psychosocial conditions, conflicts, and traumata is inevitable. Of course it partly depends on the theoretical assumptions and etiological models of the different psychotherapeutic schools (see Differential Diagnosis in Psychiatry).
Treatment Because psychological factors are most influential in the development and course of somatoform disorders they have to be addressed in every effective treatment. Of course the setting, intensity, and content of psychological interventions can vary depending on factors like severity of symptoms (duration, intensity, functional impairments), comorbidity, insight, and motivation of the patient and availability of psychotherapy. In a step-by-step approach the primary care physician should start with short-term verbal interventions. Acute and isolated somatoform symptoms may respond to psychoeducation and counseling within the usual medical visits. Counseling and advice for general and easy-to-administer methods of symptom monitoring and management can be helpful. The physician should know the pitfalls in the treatment of patients with somatoform disorders and avoid procedures, which might reinforce the patients’ pathological illness behaviors (e.g., no medical tests or laboratory examinations without clear indication). Information about and motivation for more specific
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forms of psychotherapy are essential if these basic interventions within the primary care system are not sufficient. For the more severe patients a referral to mental health experts is needed, for chronic and therapy-refractory cases even psychiatric or psychosomatic inpatient treatment may be necessary. Unspecific factors, which are important in any psychotherapy (e.g., therapeutic alliance, expectations of being helped, enhancing the sense of mastery, etc.) can be differentiated from specific therapeutic techniques and be adapted to relevant pathological processes in somatoform disorders (see below). Multimodal and multidisciplinary treatment approaches seem to be more effective than single treatment approaches (Mayou et al., 1995). A validating, accepting, and (especially in the beginning) nonconfronting patient–therapist relationship is a prerequisite for active participation in therapy. It is also the basis for the development of an alternative, holistic model of illness, the motivation to change, and active participation in therapy. Selfmonitoring diaries aim at a precise identification of symptoms in relation to external or interoceptive stimuli, events, and their positive and negative consequences in concrete situations. Psychoeducation and cognitive therapy are essential for a critical discussion and revision of inadequate concepts about health and disease and a better understanding of ongoing mechanisms. For example, the hypochondriac patient may realize the effects of a feedback loop leading to a vicious circle as is the case in increased autonomic arousal through anxious thoughts and worries about illness. In a collaborative way the therapist tries to convey a more realistic and helpful paradigm of body–mind interactions which aims at a better understanding and mastery of symptoms. Relaxation training, breathing exercises, or mindfulness-based interventions are introduced as methods for an active reduction of tension, arousal, and apprehension. The patient is motivated to reduce maladaptive illness behaviors like body scanning and checking, excessive medical visits, seeking reassurance, and social withdrawal. Cooperation with physicians and family members is warranted so that they can avoid inadequate reactions to the patients’ illness behaviors. Alternative behaviors, e.g., exercises, sports, and positive activities have to replace the symptomatic ones and can help to re-experience bodily functions in a more positive way. Stress management, social competence, and problem-solving interventions can be used optionally to improve coping with stress, conflicts, and interpersonal problems. Furthermore, therapy has to prevent relapses and enhance a more balanced life style. As some of the symptoms might resist the described interventions or take a longer time to be effective, patients have to learn how to ‘live with the residual complaints as best as possible’ and to regain a better quality of life instead of waiting for complete remission. Up to now there is no empirically validated form of specific pharmacological therapy. Clinical experience shows that in some cases tricyclic antidepressants and selective-serotonininhibitors might be helpful, especially in patients with comorbid depression, anxiety disorders, and pain. However, without concomitant psychotherapy the risk of relapse is usually high. Benzodiazepines and low-potency neuroleptics should not be given because of the risks of long-term intake, especially abuse and dependency in benzodiazepines and tardive dyskinesia in neuroleptics.
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Somatoform Disorders
Compared to other psychiatric disorders the empirical evidence for effective treatments is still low in somatoform disorders. But there is a growing number of controlled outcome studies since the syndromes were clearly defined in 1980. These studies have to face the fact that most of these patients are not treated within mental health services but in the primary care system or in consultation and liaison services. Additional difficulties arise from the complexity of recent approaches, which can only be evaluated as ‘total treatment packages’ (see Antidepressant Drugs; Behavior Therapy: Psychiatric Aspects).
Summary and Outlook The clearer operationalization of diagnoses within DSM and ICD classification systems stimulated a lot of empirical studies concerning the epidemiology, etiology, pathogenesis, and treatment of somatoform disorders in the last three decades. Medical and mental health services have realized the clinical relevance of these disorders and the need for early recognition, collaborative, stepped-care, and multidisciplinary intervention programs (Schaefert et al., 2012). Clinical observations and outcome studies have challenged the former statement, that patients with somatoform disorders in general have a poor prognosis. The acceptance of empirically based psychotherapeutic and psychiatric interventions can be enhanced if their positive effects are transparent to the patient. Convincing models for a better explanation and understanding of symptoms, the definition of limited and concrete treatment goals, and the provision of successful experiences in symptom reduction and improving coping abilities may have the function of a ‘positive vicious circle’ and convey a sense of mastery. However, patients and their caregivers have to overcome a series of obstacles: 1. The first step is the correct recognition and early diagnosis by the primary care physician. 2. Divergent health belief systems of patient and physician may burden the relationship and cooperation between them, so that it is difficult to realize psychological interventions. 3. Although psychological treatment is indicated, physicians often avoid time-consuming verbal interventions or are not adequately trained for their application. However, it is not clear whether psychotherapeutic interventions, which are proven within a psychotherapeutic context, can be adopted to primary care without diminishing their efficacy. 4. If physicians try to refer to mental health experts a lot of patients refuse this referral (e.g., for reasons of stigma) or are not motivated for psychotherapy. Since empirical validation of treatment approaches for subtypes of somatoform disorders is still different, the selection of therapeutic methods often depends on local availability and personal preferences rather than on evidence-based criteria. Each of these items is a challenge for clinical and research efforts as well as for a better dissemination of existing knowledge and competence to different health professionals who are involved in the treatment of somatoform patients. Since the first edition of this text a lot of empirical studies have
contributed to our knowledge and are congregated in some meta-analyses and Cochrane reviews. In the last decade a controversial debate concerning the nosological congregation in somatoform, related disorders and their diagnostic criteria (Rief and Hiller, 1999) was ongoing. Since the introduction of the modified concept of ‘somatic symptom disorder’ in DSM-V it is even more pronounced. Especially the elimination of the requirement that symptoms must be ‘medically unexplained’ is criticized. Prominent researchers call the DSM-V concept as poorly tested and as too ‘loose’. In the case of ‘false positive diagnosis’ the patient has to bear the burden of severe or harmful consequences, especially if underlying medical causes are missed and not treated adequately. Additionally many patients maybe ‘mislabeled as mentally ill’ (Frances, 2013). High rates of mutual comorbidity between anxiety, affective, substance abuse, and somatoform disorders have challenged the usefulness of the concept of discrete and stable nosological entities and different treatment needs. Some clinicians had proposed a concept of spectrum disorders with more transient borderlines between different, but obviously linked, clusters of psychopathology and their courses in a long-term perspective. Specifically the relevance of subclinical forms of disorders as precursors and remaining psychopathological states after partial remission is stressed. Some recent candidates are thought to be potentially affiliated as psychiatric diseases with apparent parallels to somatoform disorders. Chronic fatigue syndrome, fibromyalgia, and multiple chemistry sensitivity, etc. are syndromes with bodily complaints of unknown etiology and pathogenesis. Their treatment might profit from adopting interventions, which have been successfully applied in somatoform disorders.
See also: Fear: Psychological and Neural Aspects; Freud, Sigmund (1856–1939); Hysteria: History and Critiques; Janet, Pierre (1859–1947); Normality and Mental Health; Psychosomatic Medicine; Stress, Coping and Health.
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